Will Sheff, the force behind Austin’s Okkervil River , is not one to take baby steps. He conceives the band’s music in broad, ambitious strokes, and if what he hears in his head is beyond his vocal range, no matter. He goes for it. At first his yelping had a “little engine that could” quality to it, but as he’s learned to work within his limitations, this overreaching has given the group a thrilling and formidable determination. The Stage Names (Jagjaguwar) could not be more dissimilar to the last Okkervil album: It’s as rollicking and driving as Black Sheep Boy was creepy and ominous. Sheff still spills out wordy, stream-of-consciousness lyrics, but this time they’re closer to playful than ponderous. It’s a smart, deliberate move, and it yields great results. “A Hand to Take Hold of the Scene” plays like a pop hit; “Unless It’s Kicks” drives hard for the joy of it (“What gives this mess some grace unless it’s kicks”). There’s not a dud here, and after four albums, the band continues to make big leaps forward. This one is its boldest yet.